The present invention pertains to a portable environmental control system including a motor driven fan or blower, a flexible duct system and air filtration units for removing toxic and/or explosive gasses from building interior rooms and other confined spaces.
There are many situations wherein volatile, toxic and particulate laden gasses are generated or leak into an interior room of a building or other confined space. The presence of explosive gasses, such as vapors from hydrocarbon based products, as well as natural or liquefied petroleum gasses, often occur within an enclosure or confined space, such as an interior room of a building, a storage tank or the cargo hold of a ship, for example. In many instances, the generation of toxic or explosive gasses may occur in spaces which are somewhat inaccessible, such as the upper floors of a multistory building, the cargo hold of a ship, as well as many other confined spaces from which such gasses and vapors need to be safely evacuated. Volatile organic compounds such as automobile and aircraft paints, resurfacing materials, porcelain paints, reducers, glues, cleaning agents, grain dust and hydrocarbon fumes must be carefully evacuated from an interior space to avoid adverse effects, including unwanted combustion of such materials. In many instances, such materials cannot be safely or conveniently vented to atmosphere and treatment of such gaseous material may be required to occur within the interior space being evacuated of such material or a confined space generally adjacent to the space being evacuated.
In pursuing the development of the present invention, applicant has noted the dearth of portable equipment suitable for handling explosive or toxic gasses or vapors, including equipment which is essentially explosion proof and may be quickly and conveniently set up adjacent to or even placed within a confined space from which the toxic or explosive materials are to be evacuated. Commercially available motor driven blowers or fans, for example, typically are directly connected to an electric drive motor or a combustion engine. Such equipment cannot be safely placed in the confines of a space from which the aforementioned materials require evacuation. Moreover, direct connected motors tend to become severely clogged with particulate material entrained in the gases being evacuated
Another problem associated with prior art equipment for treating or evacuating volatile or toxic gasses is, as mentioned above, the lack of portability of such equipment. For example, in high rise commercial or residential buildings it is often necessary to carry out processes in performing construction work or applying finishing or refinishing materials in interior rooms, which processes and materials generate substantial amounts of toxic and/or explosive fumes. Such materials include paints and adhesives, for example. These materials cannot be evacuated directly to atmosphere either as a consequence of environmental regulations or because of the construction of the structure from which the material is to be removed. Accordingly, there has been a long-felt need to develop portable equipment which may be taken into generally inaccessible, confined interior spaces within a building or vessel, for example, and erected for evacuating gasses from such spaces without discharging the evacuated gasses untreated into an adjacent confined space and without discharging such materials untreated directly to atmosphere exterior of the structure being evacuated.
Although certain types of filters such as so-called HEPA filters are available for certain types of ventilation systems, the volumetric flow rate capacity of such filters is relatively low and such filters cannot, typically, be used in applications wherein a high volumetric flow rate of toxic gas laden air must be treated and treated rapidly. Accordingly, prior art fume or gas evacuation type environmental control systems are not suitable for hazardous or explosive environments, are not actually portable and cannot be easily moved by personnel who may be required to take action in performing a number of functions quickly in a hazardous situation, such personnel including firemen or utility technicians, for example. Portability is also a major concern with regard to the provision of environmental control systems of the general type associated with the present invention because of the short time frame available to set up and operate the equipment in areas wherein high concentrations of toxic or explosive gasses may be present.
Accordingly, there has been an acute need to develop a more efficient and less hazardous system for handling various types of toxic and explosive gasses and vapors, particularly with regard to interior spaces which may, in many instances, be somewhat inaccessible. It is to these ends that the present invention has been developed.
The present invention provides an improved portable environmental control system, particularly adapted for evacuating volatile, toxic, particulate laden or otherwise potentially explosive gasses and vapors from an interior room or confined space within a building or other structure.
In accordance with one aspect of the present invention a portable environmental control system is provided which is adapted to evacuate toxic or explosive gasses or vapors from a confined space while minimizing the chance of ignition or combustion of the vapors or gasses being handled by the system. The portable environmental control system contemplates the provision of one or more sections of elongated flexible duct adapted to be connected to an indirect drive type motor driven fan or blower unit, which is rated by regulatory authorities for hazardous conditions, for conducting vapors from an interior space to a portable filtration unit or directly vented to atmosphere, when permissible or necessary in emergency situations.
A portable blower unit in accordance with the invention preferably utilizes an axial flow electric motor driven fan which includes drive mechanism and a location of the electric motor on the blower unit which is isolated from gasses or vapors being handled by the system so as to minimize an unwanted source of ignition. The portable blower unit is also adapted to utilize conventional household electric power sources or higher voltage electric power sources by providing connections to the blower unit for each of the sources via elongated power cords. The power cords are configured to minimize the chance of generating a source of ignition for volatile gasses or vapors being handled by the system, are enclosed in a flame and abrasion resistant sleeve and are preferably fire resistant rated by authorities, such as Underwriters Laboratories, Inc. (UL)
In accordance with another aspect of the present invention a portable environmental control system is provided for evacuating and treating various gaseous materials whereby air which entrains the gaseous materials may be returned to the general vicinity of the interior space from which the gasses or vapors are evacuated. In this way the system of the invention may be disposed in the confines of a space being treated or disposed in an enclosed space directly adjacent to a space being treated without discharging unwanted gasses or vapors into other parts of a building or other structure. The system includes a portable plenum and one or more gas filtration units which may be easily transported to or from, erected or assembled and collapsed or disassembled within a confined space, such as an interior room of a high-rise building or the like, or a cargo hold of a ship or a cabin or cargo hold of an aircraft, for example.
In accordance with still a further aspect of the invention a compact multi-stage filter cabinet is provided which may be adapted for use with a large plenum or filter unit or may also be positioned in a window or other opening for venting treated air directly to atmosphere from an interior or confined space which is being evacuated of toxic or explosive vapors or gasses.
Still further, the invention provides a high volumetric capacity, lightweight, portable environmental control system which may be easily transported to the site of an interior room or space from which gaseous materials are to be evacuated at a high volumetric flow rate and utilizing conventional low or intermediate voltage electric power sources. The environmental control system of the present invention may be easily used in interior rooms of a high density dwelling unit structure, such as a hotel or apartment complex or within dangerous, confined spaces such as a storage tank, the cargo hold or space of a ship, other surface transportation vehicles or aircraft.
Those skilled in the art will further appreciate the above-noted advantages and superior features of the invention together with other important aspects thereof upon reading the detailed description which follows in conjunction with the drawings.